A local and global tour on MOMoT

Software and Systems Modeling - Many model transformation scenarios require flexible execution strategies as they should produce models with the highest possible quality. At the same time,...     

The G-Protein-Coupled Estrogen Receptor (GPER/GPR30) in Ovarian Granulosa Cell Tumors

Ovarian granulosa cell tumors (GCTs) are thought to arise from cells of the ovarian follicle and comprise a rare entity of ovarian masses. We recently identified the G-protein-coupled estrogen receptor (GPER/GPR30) to be present in granulosa cells, to be regulated by gonadotropins in epithelial ovarian cancer and to be differentially expressed throughout folliculogenesis. Thus, supposing a possible role of GPER in GCTs, this study aimed to analyze GPER in GCTs. GPER immunoreactivity in GCTs (n = 26; n (primary diagnosis) = 15, n (recurrence) = 11) was studied and correlated with the main clinicopathological variables. Positive GPER staining was identified in 53.8% (14/26) of GCTs and there was no significant relation of GPER with tumor size or lymph node status. Those cases presenting with strong GPER intensity at primary diagnosis showed a significant reduced overall survival (p = 0.002). Due to the fact that GPER is regulated by estrogens, as well as gonadotropins, GPER may also be affected by endocrine therapies applied to GCT patients. Moreover, with our data supposing GPER to be associated with GCT prognosis, GPER might be considered as a possible confounder when assessing the efficacy of hormone-based therapeutic approaches in GCTs.     

Poly(3-hexylthiophene)/C60 heterojunction solar cells: Implication of morphology on performance and ambipolar charge collection

The performance of heterojunction organic solar cells is critically dependent on the morphology of the donor and acceptor components in the active film. We report results of photovoltaic devices consisting of bilayers and bulk heterojunctions using poly(3-hexylthiophene) (P3HT) and Buckminsterfullerene C₆₀. White light power efficiencies of η2.2% (bulk heterojunction) and 2.6% (bilayer) were measured after a thermal annealing step on completed devices. Optical and structural investigations on non-annealed bilayer thin films indicated a distinct porosity of the spin-coated polymer, which allows C₆₀ to penetrate the P3HT layer and to touch the anode. This resulted for these bilayer solar cells in the experimental observation that electrons were collected predominantly at the cathode after photo-excitation of P3HT, but predominantly at the anode after C₆₀ excitation. A morphological model to explain the ambipolar charge collection phenomenon is proposed.     

Changes in sympathetic nerve activity of the mammalian ovary during a normal estrous cycle and in polycystic ovary syndrome: Studies on norepinephrine release

Although it has been known for many years that the ovary is innervated by catecholaminergic nerve fibers and much experimental evidence has strengthened the notion that catecholamines are physiologically involved in the control of ovarian function, scarce evidence has been presented as to the role of sympathetic activity in ovarian pathologies that affect reproductive function. The purpose of this article is to provide a succinct overview of the findings in this area and discuss them relative to the pathology of polycystic ovary syndrome, the most common ovarian pathology in women during their reproductive years.     

Ovarian acetylcholine and muscarinic receptors: hints of a novel intrinsic ovarian regulatory system

More than two decades ago, the degrading enzyme of the neurotransmitter acetylcholine (ACH) was reported in nerve fibers of the rat ovary. Subsequently, it was assumed that ACH is a neurotransmitter of ovarian nerves, although the sole presence of the degrading enzyme, ACH-esterase, does not allow such a conclusion. That ACH may be involved in the complex regulation of ovarian functions, including hormone production, was indicated by studies using, for example, granulosa cells (GCs). The lack of detailed information about both source(s) and functions of ACH in the ovary prompted us to examine sites of ovarian ACH-synthesis and ACH-receptor-bearing target cells. We also started to identify functions of ACH in cultured human GCs. While ovarian innervation and recently described neuron-like cells of the ovary were not immunoreactive for the ACH-synthesizing enzyme, choline-acetyl transferase (CHAT), we found immunoreactivity in GCs of rodents and primates. Isolated human and rat GCs produced ACH and contained the vesicular ACH transporter (VACHT). These results indicate that endocrine GCs are an unexpected non-neuronal source of ACH in the ovary. Moreover, these cells and GCs in vivo contain ACH-receptors of the muscarinic subtype (MR), namely M1R and M5R. In contrast, oocytes express M3R. MR of human GCs are functional and cholinergic stimulation is linked to rapid increases in intracellular Ca(++) levels. M1/5R activation also led to increased cell proliferation of human GCs in vitro and this stimulatory effect was found to be associated with rapid disruption of gap junction communication. Ongoing studies begin to identify regulation of ion channels and altered gene expression as consequences of MR stimulation. Thus, our results outline first details of an unexpected intraovarian, non-neuronal cholinergic system, and suggest that it may be involved in the regulation of cell proliferation in the ovary.     

How people interpret conditionals: Shifts toward the conditional event.

We investigated how people interpret conditionals and how stable their interpretation is over a long series of trials. Participants were shown the colored patterns on each side of a 6-sided die and were asked how sure they were that a conditional holds of the side landing upward when the die is randomly thrown. Participants were presented with 71 trials consisting of all combinations of binary dimensions of shape (e.g., circles and squares) and color (e.g., blue and red) painted onto the sides of each die. In 2 experiments (N? = 66, N? = 65), the conditional event was the dominant interpretation, followed by conjunction, and material conditional responses were negligible. In both experiments, the percentage of participants giving a conditional event response increased from around 40% at the beginning of the task to nearly 80% at the end, with most participants shifting from a conjunction interpretation. The shift was moderated by the order of shape and color in each conditional's antecedent and consequent: Participants were more likely to shift if the antecedent referred to a color. In Experiment 2 we collected response times: Conditional event interpretations took longer to process than conjunction interpretations (mean difference = 500 ms). We discuss implications of our results for mental models theory and probabilistic theories of reasoning. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Visualizing the expression of a human growth hormone (hGH) transgene in the liver: intrahepatic regional and intracellular differences of expression are associated with morphological alterations and hepatocellular proliferation

Growth hormone acts directly on liver cells; it binds to its receptor and induces a multitude of intracellular events leading, for example, to the production of insulin-like growth factor-1 (IGF-1). While much is known about the biochemical side of these events, their structural correlates are less well examined. Here, we examined livers of transgenic mice (TM) expressing human GH, in an attempt to correlate at the cellular level the site of GH gene expression with effects on morphology and mitotic behavior of liver cells within the hepatic architecture. Using in situ hybridization histochemistry we observed a striking expression pattern of the hGH gene in hepatocytes near the periportal spaces. In the same regions, the hGH protein, but no IGF-1 immunoreactive product, was detected using immunohistochemical methods. In the sections of TM livers, 6.8-31.9% of cells were hGH-immunoreactive. However, the cellular hGH staining pattern was not homogeneously distributed in the immunoreactive cells. Two main patterns became obvious. In the majority of the immunoreactive cells a cytoplasmic stain was present. These cells exhibited normal liver cell features and were not enlarged (type I). In the other group (type II), the staining was stronger and concentrated, sometimes punctuate, and often confined to cytoplasmic compartments which were in a perinuclear position. The latter staining pattern was generally seen in morphologically altered cells, which were enlarged and possessed intranuclear inclusions and invaginations. In the the periportal regions, mitotically active hepatocytes were evident, but these cells, as judged from immunocytochemistry, apparently did not express the transgene. In conclusion, different staining patterns for hGH may indicate different levels of transgene expression, which could be associated with difficulties in the cells with regard processing and/or secreting the hormone. In addition to the endocrine actions implied by the high hGH levels in the peripheral circulation of these TM, intracrine actions are also suggested (type II staining pattern), but para- and autocrine loops are possible as well (type I staining pattern). Whether IGF-1 is involved, and the mechanism underlying hepatocyte cell proliferation, remain to be examined.